As communication devices continue to evolve, device capabilities continue to expand. One such capability is dual band operation which allows a communication device, such as a portable radio, to operate over two independent frequency bands, for example a UHF band and a GPS band. The ability to provide dual band operation presents challenges to designers in terms of performance, robustness, reliability and manufacturing costs. The end user of the communication device desires simple operation without user intervention.
A variety of antenna configurations have attempted to address the need for dual band UHF/GPS operation, each configuration plagued with issues. For example, a folded sleeve monopole antenna configuration faces issues with length because the overall finished antenna length can not be shorter than one electrical length at the GPS frequency. Another approach to dual band UHF/GPS operation utilizes a concentric monopole having a quarter wavelength at GPS frequencies in conjunction with a helix having a quarter wavelength at UHF frequencies. However, this approach implements multiple parts increasing complexity and manufacturing cost. These prior approaches also require the use of a coaxial connector, such as SMA, TNC or mini UHF connectors, which greatly impacts overall manufacturing cost.
Accordingly, it would be desirable to have a dual band antenna that overcomes the aforementioned problems.
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